What makes people romantic? According to Seattle-based Amazon, it's buying romance novels, relationship books, romantic comedy movies, a romantic music collection (featuring Dean Martin, Barry White and Luther Vandross) and "sexual wellness products." Based on these criteria, and per-capita sales data from Jan. 1, 2012 to Jan. 23, 2013, here are the 20 most romantic U.S. cities with more than 100,000 residents. Oh, and happy Valentine's Day.

20. Billings, Mont. Well, they've got to do something to stay warm and active during those long, cold winters. less

"Romantic" might not be the exact word. In addition to this third-place finish for romance, Miami was America's sexiest city for the fourth year in a row, thanks to its prowess in the "sexual wellness" category, according to Amazon. (Cambridge, Mass. and Alexandria, Va. were second and third in that area.)

"Romantic" might not be the exact word. In addition to this third-place finish for romance, Miami was America's sexiest city for the fourth year in a row, thanks to its prowess in the "sexual wellness"